To make the reciprocal of a fraction, swap the numerator and denominator.
The reciprocal of 3/4 is 4/3.
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To make the reciprocal of an integer, write it as a fraction, then proceed as above. Example: (reciprocal of 2) = (reciprocal of 2/1) is 1/2.
Not surprisingly, the reciprocal of a number x is written 1/x.